This invention relates generally to underfloor electrical distribution systems, and, more particularly, to an improved underfloor preset housing. Modern office buildings require electric power, communication, and computer data services in various combinations at a large number of locations. In many instances these needs are addressed by underfloor distribution systems consisting of a network of ducts or raceways that are mounted in concrete floors. Access to the underfloor service raceways is obtained through presets that are mounted on the raceways at regular intervals, usually 24 inches on center, before the concrete floor is poured. The preset defines a hollow interior compartment that is interconnected with the interior of the duct to provide access to the services that are carried in the duct. The preset includes a removable mud cap that is generally parallel to the surface of the floor and is positioned slightly below the surface of the concrete floor. The mud cap serves to prevent concrete from entering the interior compartment of the preset when the floor is poured. After the concrete floor has hardened, the concrete above the mud cap is broken away and the mud cap is removed to provide access to the interior of the preset. An activation assembly that provides for power or data outlets may then be installed on the preset.
In the past, presets have typically been connected to the ducts by swaging or pop rivets. Connecting the presets in this fashion is labor intensive and expensive, especially in large office complexes where a large number of presets is required. Additionally, if the wrong size preset is installed on the duct it is difficult to remove the preset without damaging the duct.